Narrative:

Received clnc to land on runway 18. Noted cessna (single engine piston) cleared #2 to land. Rolling wings level on base to final, TCAS alert for 'traffic, traffic' sounded, and observed visually cessna's position lights directly in front of our path. Took evasive action, called tower and announced go around due to aircraft in flight path. Tower informed us that cessna had us in sight and still cleared to land #1. At that time, we were well past the cessna, and able to safely continue approach to land. Landed without incident. Question remains, why did cessna appear in front of our flight path? Also, why did tower not inform us of cessna's position.

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Original NASA ASRS Text

Title: MDT FLC TOOK EVASIVE ACTION TO AVOID A SEL CESSNA ON FINAL AHEAD OF THEM WHEN TURNING FROM BASE LEG TO FINAL.

Narrative: RECEIVED CLNC TO LAND ON RWY 18. NOTED CESSNA (SINGLE ENGINE PISTON) CLEARED #2 TO LAND. ROLLING WINGS LEVEL ON BASE TO FINAL, TCAS ALERT FOR 'TFC, TFC' SOUNDED, AND OBSERVED VISUALLY CESSNA'S POSITION LIGHTS DIRECTLY IN FRONT OF OUR PATH. TOOK EVASIVE ACTION, CALLED TWR AND ANNOUNCED GAR DUE TO ACFT IN FLT PATH. TWR INFORMED US THAT CESSNA HAD US IN SIGHT AND STILL CLEARED TO LAND #1. AT THAT TIME, WE WERE WELL PAST THE CESSNA, AND ABLE TO SAFELY CONTINUE APCH TO LAND. LANDED WITHOUT INCIDENT. QUESTION REMAINS, WHY DID CESSNA APPEAR IN FRONT OF OUR FLT PATH? ALSO, WHY DID TWR NOT INFORM US OF CESSNA'S POSITION.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.